An imaging apparatus is a device commonly utilized to create an image on a sheet of media. An imaging apparatus may be provided with a stack of individual sheets of media, a media tray, a pick mechanism and a lift plate. The stack is commonly located on the lift plate. The lift plate may be part of the media tray. The media tray may be permanently attached to the imaging apparatus, or may be removable from the imaging apparatus. The lift plate commonly moves the stack towards the pick mechanism. The pick mechanism can remove one sheet from the stack and introduce it to the imaging apparatus. While the single sheet of media passes through the imaging apparatus, the image may be formed thereon.
As sheets of media are sequentially picked by the pick mechanism and processed by the imaging apparatus, the thickness of the stack decreases. When the stack thickness is zero, media reserves have been depleted and printing must stop until the stack is replenished.
In one exemplary embodiment apparatus and methods for monitoring a stack of media contained within an imaging apparatus may include: a lift plate upon which the stack is disposed; a gate located in the imaging apparatus, the gate comprising an open state and a closed state; a first flag attached to the lift plate, wherein the first flag is positioned in the gate, the first flag comprising at least one graduation; wherein the imaging apparatus comprises a first condition and a second condition; wherein, in the first condition, the first flag graduation is located in the gate thereby placing the gate in the open state; and wherein, in the second condition, the first flag graduation is not located in the gate thereby placing the gate in the closed state.